Re: Standby recovers records from wrong timeline

At Fri, 21 Oct 2022 16:45:59 +0900 (JST), Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com> wrote in
> At Thu, 20 Oct 2022 14:44:40 +0300, Ants Aasma <ants(at)cybertec(dot)at> wrote in
> > My understanding is that backup archives are supposed to remain valid
> > even after PITR or equivalently a lagging standby promoting.
>
> Sorry, I was dim because of maybe catching a cold:p
>
> On second thought. everything works fine if the first segment of the
> new timeline is archived in this case. So the problem here is whether
> recovery should wait for a known new timline when no segment on the
> new timeline is available yet. As you say, I think it is sensible
> that recovery waits at the divergence LSN for the first segment on the
> new timeline before proceeding on the same timeline.

It is simpler than anticipated. Just not descending timelines when
latest works. It dones't consider the case of explict target timlines
so it's just a PoC. (So this doesn't work if recovery_target_timeline
is set to 2 for the "standby" in the repro.)

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center